Errors are great, but we need to know where they happened and why. This library defines functions and custom error types for annotating errors with additional context. It's like customizable stacktraces.

The primary error type, ErrorWithContext, attaches a stack of context messages to a base error. When "re-throwing" an error, use ContextualizeErrorf or one of the *ContextErrorf functions to push a message onto the context stack. Also included: convenience methods for common errors and contexts.